With fast upgrading of display products, requirements for process index are improving continuously, and a manufacturing process of an array substrate is more and more complex and fine while improving yield and quality of product. In this case, a manufacturing process of an array substrate with multiple masks is presented in the prior art. At present, manufacturing of an array substrate mainly includes the following steps of: firstly, forming a gate metal layer on a substrate and forming a pattern including a gate through a first patterning process; then, forming a gate insulation layer and a semiconductor material layer, and forming an active layer through a second patterning process; then, forming a first conductive layer, and forming a pattern including a pixel electrode through a third patterning process; and then, forming other structures such as a source and a drain, a passivation layer and a common electrode.
However, when the array substrate is manufactured by the above method, after etching the first conductive layer to form the pixel electrode, a small amount of conductive material remains in the channel region, which leads to an increasing of leak current of a thin film transistor and an abnormal voltage in a pixel area, thereby causing defects such as a contamination of display and a crosstalk.